The invention relates to a glass ceramic for dental restoration and to a method for its production.
A glass ceramic of this type is known from U.S. Pat. No. 4,798,536. This patent describes a specific porcelain material which is used as a tooth replacement material. Porcelain as a tooth replacement material has in principle been known for a long time, and is also known to be relatively susceptible to breaking. Therefore, metal substructures have generally been used in order to obtain the desired strength.
U.S. Pat. No. 4,798 536 has disclosed a porcelain material which has breaking strength properties which are such that it appears to be suitable for use as a dental material on its own.
However, it has emerged that the forces and loads which occur in the mouth may nevertheless impose loads on the material which may cause it to break.
Working on the basis of this prior art, the invention is based on the object of improving a glass ceramic of the type mentioned in the introduction in such a way that it is more resistant to breaking. A further object of the present invention is to specify a method for its production.
These objects are achieved by means of the features of claims 1 and 9, respectively.